Method of purifying water electrolytically.



H. B. HARTMAN. METHOD of PURIPYING WATER ELBGTROLYTIGALLY.

APPLICATION FILED MAY 22,1909.

UNITED STATES PA TENT oEEIcE.

HARRY B. HARTMAN, OF PITTSPURG, PENNSYLVANIA, ASSIGNOR TO MCDOWELLMANUFACTURING COMPANY, OF PITTSBURG, PENNSYLVANIA, A CORPORATION 0FPENNSYLVANIA.

Specification of Letters Patent.

Patented Mar. 8, 1910.

Application led Hay 22, 1909. Serial No. 497,729.

To all whom fit-may concern:

Be it known that I, HARRY B. HARTMAN, a resident of Pittsburg', in thecounty of Allegheny and State of Pennsylvania, have invented a new anduseful Improvement in Methods of Purifying Water Electrolytically, (Case2,) of which the following is a specification.-

This invention relates to the method of purifying water4 and otherliquids electrolytically in which the liquid is subjected to the actlonof an electric current flowing alternately and equally between metallicelectrode plates, and in which the ozone or oxygen and other gases andsalts generated by the current act on the organic impurities containedin the liquid.

The object kof the invention is to provide a method of the kind named inwhich the liquid is thoroughly purified and in an economical manner.

The essential features of the method consist in making and breaking theelectric circuit to the electrode plates with the starting and stoppingof iiow of the liquid, but in a manner to maintain the circuit somewhatlonger than the flow of liquid so as to insure the full treatment of allparts of the liquid; in subjecting the liquid to several successivetreatments of the electric current and between the same mixing the water.and holding it with the confined gases and salts for such period oftime as to enable the gases to act upon the or anic matters contained inthe water; in t e use of an alternating current, or a currentperiodically re versed to flow alternately and equally in oppositedirections, in conjunction with electrodes of aluminium or anv alloy orcomposition containing aluminium, which under the action of the electriccurrent give olf aluminium Oxy-hydrate and on account of the reversalsof the current remain clean; in meelectric current.

chanically ltering the liquid so treated electrolytically. in order toseparate there from the coagulum and fiocculent precipitates; and inother process steps hereinafter described and claimed.

.The accompanying drawing shows a. sec tional diagram of apparatussuitable\for carrying outthe invention. 4 l illustrates the electrodebox in which the liquid is subjected to the Aaction of an This box isshown as pro'- the second grou o f plates.

vided with a plurality of sets of electrode plates, each set being shownas consisting of three plates, namely the outside plates 2 and anintermediate plate 3, said plates be- `lng so arranged that the liquidenters at the upper end of one outside plate, as at 4.-, thence flowsdownwardly between said plate and the intermediate plate, underneath thelatter, as at 5, thence up between said intermediate plate and the otheroutside plate and over the top of the latter, as at 6. The inlet to theelectrode box is at 7 and the outlet is at 8 on the opposite side or endand at the top, so that the box is always full of liquid and the platesentirely covered. The plates are so set in the box that the liquidcannot escape around the edges, but is compelled to take the courseindicated. The plates are set in the lining 8a which is separated fromthe iron box by the insulation 8*. Between the two sets of electrodes isa space 9 of very materially greater cross-sect1onal area. than thespaces etween the electrode plates so that the liquid passes through thesame at a very much reduced rate of flow in order that the gasand saltsgenerated between the plates have time to act upon the impurities in theliquid, and particularly to permit the oxygen or ozoneY generated tocoagulate theorganic matters in the liquid. 'lhis space may be termed a.reaction or coagulation chamber. The box is tightly sealed in order thatthe vgases cannot escape, but are confined in the liquid. In order tomix the liquid and gases in this space it is divided by means of plate10 projecting from thetop downwardly toward the bottom so as to compelthe liquid to iow down underneath the same and thence up to The boxshown is provided wit two groups or sets of electrode plates and a sinle intermediate mixing space, but obviouy any desired nnmber of groupsof lates may be rovided, and any deslred o d number of p ates may beused in each group.

The particular box illustrated is similar to that shown, described andclaimed in my' application filed concurrently herewith, Serialv No.497,732, but the present method is not, limited to the use of t isspecilc box, it being sufficient to provide any form of sealed boxhaving therein a plurality of sets of -electrodes in order to givesuccessive rlhe electrode plates are formed of aluminium or of analuminium alloy or composition, which under the action of the electriccurrent gives oif Oxy-hydrate of aluminium which is insoluble in waterand -forms a ilocculent precipitate with the 1mpurities in the water.

In conjunction with such aluminium containing plates l use either analternating current, or at least a periodically reversing current suchas described in my application Serial N o. 418,745, filed March 2, 1908,which currentl is reversed in a manner to cause the current to flowalternately in opposite directions for equal or uniform periods of timeduring the How of the liquid. In the present instance there isillustrated a source of alternating current, such as the alternatinggenerator shown at 12 which is connected by mains 13 and 14 toconnections 15 and 16 respectivelyT to the outside plates 2 of eachgroup of electrode plates. No electrical connection is made to theintermediate plate or plates of each group, but the latter in eachinstance become bi-polar. rent iiowing alternately and equally inopposite directions between the plates keeps4v the plates clean, thedeposit which forms thereon being merely soft and slushy so that itsloughs off from time to time. Consequently the plates at all timesdevelop their maximum efficiency and develop a large percentage ofaluminium Oxy-hydrate. The plates, of course, can be cleaned f rom timeto time and for this purpose flushing outlets closed by valves 16a areprovided in the bottom of the electrode box underneath each set ofelectrodes, and another flushing outlet closed by valve 16b is providedin the bottom of the reaction and coagulation chamber 9.

In order to economize in current the circuit to the electrode box ismade and broken with the starting and stopping of ow of the liquidthrough the apparatus, and this is effected in a manner to maintain thecurrent flow somewhat longer than the liquid flow. Various forms ofapparatus to eectthis purpose may be usedh As shown in the dra-win sthis circuit interrupter is arganged to brea both sides of the circuitbetween relatively stationary metal contacts 22 and carbon contacts 22aand movable metal contacts 23 and carbon contacts 23a. The carboncontacts 22a are slidably mounted in their holders so as to permit thecircuit to be made and broken between the carbon contacts before it ismade and broken between the'metal contacts, thereby overcoming the evileects of arcing. The movable contacts areconnected to means whereby thecircuit is closed upon the be inning of low of liquid" through the puriing apparatus, but

The curbanali slightly before such flow begins, and is broken by theinterruption of liquid flow but somewhat later than the cessation ofsuch flow, in order to insure the roper electrical treatment of allliquid lowing through the electrode box. The particular mechanism foreffecting such making and breaking of the circuit which is illustratedin the drawings is similar to that shown and described in my applicationiiled concurrently herewith, Serial No. 497,730, and is as follows: Inthe service pipe 24 is a valve casing 25 having an inlet 26 and'outlet27 with a valve 28 normally closing communication between the inlet andoutlet. In the upper part of the casing is a piston 29 provided with ayoke 30 having a sliding fit on stem 31 cf the valve. Said stem at itsupper end is provided with a nut or head 32 which limits the amount ofidle or lost-motion movement which the piston may have upwardly withoutlifting the valve 28 from its seat. The chamber above the piston isconnected by relief passage 33 with the outlet side of the casing andthe piston is also provided with a small equalizing port 34. Connectedto the piston is 'a rod 35 projecting up through a stuiling box in theupper end of the casing and through the upper end of a bracket. 36. Thisrod and the piston are normally held depressed by a helical compressionsp1-ing 37 surrounding the rod between the bracket 36 and an adjustablecollar 38 secured to said rod. Secured to the rod 35 above the bracketis a cone-shaped 'body 39 which in the upward movement of -the rodcontacts with and carries with said rod the cross-head 40 carrying themovable contacts 23 and which cross-head is slidably mounted on saidrod. A helical compression spring 41 is put under compression when thecross-head moves upwardly. When` fully elevated the crosshead is lockedin position to hold the current closed by means of trigger 42 which isheld by a suitable spring in engagement with said cross-head and whichis provided with a rojecting portion in position to be engage by thecone-shaped body 39 as the latter approaches the limit of its downwardmovement. The operation of this circuit maker and breaker is as follows:When the service pipe is closed `and no water is flowing through theapparatus the valve 28 is seated, the piston 29- is in its lowestposition and the circuit is broken. As soon as the service pipe isopened the pressure above the piston 29 is instantly relieved throughpassage 33 and consequently said piston is forced upwardly. This carriesthe cross-head 40 upwardly and closes the circuit between the terminals22 and 23. These terminals contact before the lost-motion between thepiston yoke 30 and valve stem head 32 is entirely taken up. The furtherupward movement of pistony 29 brings the yoke 30 into cont-act with thehead 32 of the valve stem 22 and 23 before the valve 28 was opened,

one set of said terminals being mounted to slide to allow for thefurther movement of the piston 29 and cross-head 40. after the terminalscontact. As soon as the service pipe is closed the pressure backs upthrough relief passage 33 above the piston 29 and brings said pistondown quite sharply until the valve 28 seats. The closing of valve 28cuts off communication between the supply side of the casing and thepassage 33 so that further equalization cannot take place through saidrelief passage 33, and the subsequent equalization to permit the pistonto come fully down must take place through the small leak port 34. ,Thisis so small that the piston descends further slowly under the action ofspring 37. Meanwhilev the crosslea-d remains in elevated position bytrigger 42 for a considerable period of time after the valve 28 isseated and until the piston 29 approaches the limit of its downwardmovement, when the cone 39 contacts with the projecting portion of thetrigger and releases the same from the cross-head. This permits spring41 to snap the cross-head downwardly and break thc circuit.

The circuit controller described operates entirely automatically to makeand break the circuit by the turning on and off the water or otherliquid being purified, but in such a manner that the current through theelectrode box is established before Iany liquid begins to fiow throughthe same, and the breaking of the circuit is retarded for some timeafter the liquid ceases to ow through the electrode box. Consequently itis not possible for any liquid to escape treatment by the electriccurrent for an adequate period of time to destroy all of the organicmatter therein.V

From the electrode box the liquid passes through pipe 45 to the lowerend of a vertical reaction and ozoning chamber 46 through which it risesand thence passes by pipe 47 to a four-way valve 48 which normally isset to direct the water through pipe 49 to the upper end of-a mechanicalfilter 50. To the lower end of said filter is connected a pipe 51leading to three-way valve 52 which normally directs the li uid tovertical pipe 53 also connected to the our-way valve 48 and the latterbeing connected by fpipe 54 to the upper end of the mechanical lter 55.The lower end of the latter filter is connected to 'a tee 56 to which isconnected a pipe 57 leading to the three-way 'valve 52, and the servicepipe 24 is also' connected to said tee. A flushing pipe 60 provided withvalve 61 is 'connected to pipe 53. The filters 50 and 55 may be of anydesired kind of -the filter 55 with charcoal or the like.

mechanical filters. Preferably the filter 50 will be filled with fine`quartz or sand and In the normal position of the four-way valve 48 andthree-way valve 52 as shown the liquid is-conducted through filters 50and 55 in succession flowing downwardly throu h each filter. By changingthe position of tie three-way valve 52 and opening the fiushing valve 6lthe liquid from the lower end of filter 50 passes through the three-wayvalve 52 and pipe 57 to the lower end of filter 55 and upwardly throughthe latter and then through pipe 54, four-way valve 48 and pipes 53 and60 to the flushing outlet, it being understood that the service spigotsare meantime closed. By reversing the fourway valve 48 and changing theposit-ion of the three-way valve 52, as above, the liquid coming throughpipe 47 passes downwardly through `filter 55 and thence by pipe 57*through the three-way valve 52 through pipe 51 into the lower end offilter 50, thence upwardly through the latter and by pipe 49 to four-wayvalve 48 and thence throughv pipes 53 and 60 to the flushing outlet. Inthis manner each of the filters can be separately washed by clean liquidcoming through the other filter. j

The method described provides for the com lete and thorough purificationof the liquid with a minimum of electric current, but in a manner toinsure all portions of the vliquid being acted upon by said current.

2. The method of purifying liquids consisting in causing the liquid toflow between metallic electrodes and there subjecting the same to theactionof an electric current flowing alternately and equally in oppositedirections, and making and breaking the elec- 12o tric circuit whenstarting and stopping the flow of the liquid and in a manner to maintainthe current flow appreciably longer than the liquid flow.

3. The method of purifying liquids consist-ing in causing the liquid tofiow between metallic electrodes and there subjecting the same to theaction of an electric current, making the'circuit when starting theliquid' flow, and breaking the circuit when stopping the liquid flow butslightly later than the latter.

4. Themethod of purifying liquids consistin in causing the liquid toflow between metal ic electrodes and there subjecting the same to theaction of an electric current owing alternately in opposite directions,making the electric circuit` when starting the liquid flow, and breakingthe circuit when stopping the liquid flow, but slightly later than thelatter.

5. The method of purifying liquids consisting in causing the liquid toflow between metallic electrodes and there subjecting the same to theaction of an alterna-ting electric current, and making and breaking theelectric circuit when starting and stopping the flow of the liquid andin a manner to maintain the current flow appreciably longer than theliquid flow.

G. The method of purifying liquidsconf/ sistin in causing the liquid toflow between metal ic electrodes and there subjectingV the same to theaction of an alternating electric current, making the electric circuitwhen starting the liquid flow, and breaking the circuit when stoppingthe liquid How but later than the latter.

7. AThe method of purifying liquids consisting in causing the liquid toflow between electrodes containing aluminium and there subjecting thesame to the action of an electric current, and making and breaking theelectric circuit when starting and stopping the How of liquid and in amanner to maintain the current flow a'ppreciably longer than the liquidiow.

8. The method of purifying liquids consisting in causing the liquid toflow between electrodes containing aluminium and there subjecting thesameto the action of an alternatlng electric current, and making andbreaking the electric circuit when starting and stopping the iow ofliquid and in a manner to maintain the current flow appreciably longerthan the liquid flow.

In testimony whereof, I have hereunto set F. W. WINTER.

